Referring to a discussion she had with Mr Corbyn, she said: "I distinctly remember it being said that it would be appalling if staff in the Leader's Office intervened or had a role in complaints.

"I was given categorical assurances that this does not happen and has never happened.

"However, it is clear from the whistleblower's account [in the Observer] that your staff did intervene and have had a direct role in complaints."

Dame Margaret also says she is disappointed that Labour peer Lord Falconer is being considered to lead an investigation into anti-Semitism in the party.

Image copyrightAFP/GettyImage caption
Luciana Berger left Labour, claiming the party was institutionally anti-Semitic

Dame Margaret told BBC Radio 4's Today that Mr Corbyn had given her "absolute, copper-bottomed undertakings that there was no interference in the complaints process by his inner circle, by his top team".

However, she claimed "a whole number of his top team, not just one person, lots of them" were involved in decisions about individual complaints, adding: "They interfere and they lower the sanctions. People aren't suspended, they're just given a warning letter.

"What is so awful about this is that Jeremy always proclaims zero tolerance of anti-Semitism. When it comes to the actual cases, if they're his mates he doesn't demonstrate zero tolerance."

She added she had seen "so much evidence" of political interference, adding: "Trust in him is gone."

Dame Margaret also questioned whether Lord Falconer was the appropriate person to conduct an inquiry into the party's handling of anti-Semitism allegations.

'Chakrabarti fiasco'

The former Lord Chancellor is considering whether to take on the role and wants reassurances from the party that he will be given the resources he says he needs.

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Labour is seeking to appoint Lord Falconer to carry out an inquiry

He has said he wants to examine claims Labour is institutionally anti-Semitic and how to restore faith in the party's disciplinary procedures.

He told BBC Radio 5's Pienaar's Politics many Labour members believed the treatment of cases depended on "who your friends are".

But Dame Margaret said she did not think Lord Falconer was independent enough.

She claimed his inquiry could be a repeat of the one carried out by Labour peer Baroness Chakrabarti in 2016, which found that the party was 'not overrun by anti-Semitism'.

She claimed Lord Falconer had "bombarded" her with phone calls last summer, when she was facing disciplinary action - later dropped - over an angry confrontation with Mr Corbyn, to try to "force me to give an apology".

In response, Lord Falconer said: "I am shocked she thought I was trying to pressurise her into apologising for calling Jeremy Corbyn and anti-Semite. I was just trying to urge the party to drop their complaint against her."

He told BBC Politics Live presenter Jo Coburn he would be independent of the leadership and investigate any complaints of anti-Semitism in the strongest possible way, but he had not yet accepted the job.